CUET · CHEMISTRY · PYQ PAPER 2023
Read the following passage given below and answer the question.
Aldehydes and ketones undergo nucleophilic addition reactions. A nucleophile attacks the electrophilic carbon atom of polar carbonyl group from perpendicular to plane of \(sp^2\) hybridised orbitals of carbonyl carbon. The hybridisation of carbon changes from \(sp^2\) to \(sp^3\) and a tetrahedral alkoxide intermediate is formed. This captures \(H^+\) to give neutral product. In carboxylic acids, carbonyl carbon is less electrophilic than carbonyl carbon in aldehydes and ketones.How will you convert acetaldehyde to lactic acid ?
- A treating with HCN followed by hydrolysis
- B treating with \(CH_3OH\) molecules twice
- C treating with sodium bisulphite and then hydrolysing
- D treating with \(CH_3MgBr\) followed by hydrolysis
Answer & Solution
Correct Answer
(A) treating with HCN followed by hydrolysis
Step-by-step Solution
Detailed explanation
\(CH_3CHO + HCN \rightarrow CH_3CH(OH)CN\) \(CH_3CH(OH)CN + 2H_2O \xrightarrow{H^+} CH_3CH(OH)COOH + NH_3\)
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